From the pictures, they look like Taxi vinyl seat covers. I agree with Mark - this is a total waste of money. In my mind, first class on a train implies that you have only three seats across the train instead of 4.
This is just a means of tarting up the existing offering - probably because of complaints from people who were paying a first-class premium and not getting what they had paid for. If they aren't going to properly convert these to first, they should just re-designate the car a quiet car, not allow any child fares in it and charge a fiver extra for entry.